Knob Mortise Locks

Knob-operated mortise locks for internal room doors, bedroom doors, and secondary entrance doors in Indian homes and commercial buildings — T21's knob mortise lock collection covers mortise lock sets where a round knob handle operates the latch mechanism. Knob mortise locks use the same mortise pocket installation as lever mortise locks but with a round knob spindle engagement — the latch retracts when the knob is turned and the deadbolt is engaged by key. Standard 60mm backset. Compatible with all round knob handle sets in T21's range. GST invoice available. Delivered all over India, dispatched from Bengaluru.

Knob mortise locks are the traditional specification for Indian bedroom and internal room doors where a round knob handle is preferred over a lever — either for design reasons or compatibility with existing fittings. The functional difference between a knob and lever mortise lock is purely the handle operation mechanism — the internal mortise body, deadbolt, and key cylinder are identical in specification and security performance.

What is the difference between a knob mortise lock and a lever mortise lock? A knob mortise lock retracts the latch when a round knob is turned. A lever mortise lock retracts the latch when a lever handle is depressed. The internal lock body, deadbolt, and key cylinder are the same in both — only the handle engagement type differs. Knob locks suit round knob handle sets. Lever locks suit lever handle sets. Both use the standard 60mm backset for Indian residential doors.

Are T21 knob mortise locks compatible with third-party knob handles? T21 knob mortise locks use a standard spindle specification compatible with most Indian-standard round knob handle sets. Confirm the spindle diameter and length against your handle specification before ordering — particularly for doors above 45mm thickness where a longer spindle is required to reach through the full door.